Definition
Hereditary Spinal Cerebellar Ataxia
- degenerative
- onset by age 10
Epidemiology
AR
Pathology
Spinal cord shows atrophy of
- cerebellar tracts
- posterior columns
- dorsal root ganglia
- PNS
Clinical Features
Cerebellar features
- ataxic gait
- dysarthria
- tremor
- nystagmus
- difficulty with fine motor hand control
Neurological examination shows
- muscle weakness
- decreased vibration sense
- decreased proprioception
- absent DTR
- upgoing plantar response
- positive Rhomberg's Sign
May be unilateral at first but becomes bilateral
NHx
Remissions & stable periods seen
- progression usually slow
- usually confined to wheelchair by 30
NCS
Marked decreased sensory action potential
Slight decrease in motor conduction velocity
Medical Complications
Bulbar palsy / Cardiomyopathy
- either may cause death
- usually by age 40
Orthopaedic Complications
Pes Cavus
Scoliosis
Similar curve pattern to Idiopathic form
- manage similarly